<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>99乘法表</title>

    <style>
        td{
            border: 1px solid;
        }
        table{
            align-content: center;
        }
    </style>

    <script>

        document.write("<table>")

      //1.完成基本的 for 循环嵌套，展示乘法表
      for (var i = 1; i <= 9; i++) {
          document.write("<tr>")
        for (var j = 1; j <= i; j++) {
            document.write("<td>")
          document.write(i + " * " + j + " = " + (i*j) + "&nbsp&nbsp&nbsp");
            document.write("</td>")
        }
        //document.write("<br>")
          document.write("</tr>")
      }

      //2.完成表格的嵌套
        document.write("</table>")
    </script>
</head>
<body>

</body>
</html>